Reinforced plastic crate

ABSTRACT

A material handling crate having molded plastic side panels and an open top portion reinforced by an endless steel ring extending around the top of the crate and having an exposed upper surface forming at least a portion of the top surface of the rim of the crate.

United States Patent Richard F. Glldart Montebello, Cal". 842,489

July I7, 1969 Nov. 23, 1971 Rehrlg Pacific Company Los Angeles, Calif.

Inventor Appl. No. Filed Patented Assignee REINFORCED PLASTIC CRATE 6Claims, 4 Drawing Figs.

Int. Cl 865d 7/42 220/73 Field of Search [56] References Cited UNITEDSTATES PATENTS 1,207,937 12/1916 Kruse 3,341,060 9/1967 Rehrig et al.3,419,182 12/1968 Gildart 3,442,418 5/1969 Stromberg PrimaryExaminer-Joseph R. Leclair Assistant Examiner-James R. Garrett Attorney-Beveridge & DeGrandi ABSTRACT: A material handling crate having moldedplastic side panels and an open top portion reinforced by an endlesssteel ring extending around the top of the crate and having an exposedupper surface forming at least a portion of the top surfaee ot: the rimof the crate.

RGI-YIWUIW PATENTEDuuv 23 en INVENTOR RICHARD F GILDART BY 4 L y/M-ATTORNEYS REINFORCED PLASTIC CRATE This invention relates to crates, andmore particularly to crates having sidewalls molded from synthetic resinmaterials and an open top reinforced by a metal ring.

The use of material handling crates formed from synthetic resinmaterials, hereinafter referred to as plastic, is currently expandingvery rapidly. This expanded use has been, in part, made possible by thepractice of reinforcing the crates adjacent the open top portion bymetalrings or bars. This practice has been particularly useful in heavyduty crates or tote boxes such as those employed in the dairy industryor as field crates for vegetables or the like. Numerous arrangementshave been devised for reinforcing the top portions of such crates, andone such arrangement is illustrated in my prior US. Pat. 3,419,182.

While the prior art reinforcing schemes have generally been successful,it has been found that they have not been entirely satisfactory forcertain uses of heavy duty crates which are normally designed to bestacked one on top of the other in the manner illustrated, for example,in US. Pat. 3,361,292. In the prior art crates, the primary purpose ofthe reinforcing ring has been to provide dimensional stability for thetop of the crate and to reinforce the side panels to enable the crate towithstand lateral loads. While these functions of the reinforcing ringare in most cases essential, it may also be desirable to protect theplastic material at the top rim portion of the crate from damageresulting from impact loads to the top rim during handling, stacking,emptying, or cleaning of the crates. Accordingly, it is the primaryobject of the present invention to provide an improved reinforced moldedplastic crate in which the reinforcing member has an exposed uppersurface at the rim of the container to protect the plastic material atthe rim.

The foregoing and other objects are obtained in a material handlingcrate according to present invention, and including molded sidewallshaving integrally formed thereon a generally horizontal ledge extendingin vertically spaced relation below the top rim surface of the plasticsidewalls. An endless steel reinforcing ring is positioned around thecrate in contact with the horizontal ledge, with the ring extendingabove the ledge and terminating in an exposed upper edge surface. Thecrate is formed with a plurality of openings extending through theplastic walls adjacent the ledge, and a plurality of tabs are integrallyformed on the reinforcing rod member in position to extend through thespaced openings providing an interlocking arrangement retaining thereinforcing ring on the crate and in contact with a peripheral edgesurface thereof adjacent the rim of the crate.

Other objects and advantages of the invention will become apparent fromthe following specification, taken with the accompanying drawings, inwhich:

FIG. 1 is a perspective view of the top portion of a molded plasticcrate according to one embodiment of the present invention, with thereinforcing ring in position to be installed on the crate;

FIG. 2 is an enlarged fragmentary sectional view of the reinforcing ringand the crate of FIG. I after assembly;

FIG. 3 is a fragmentary elevation view of the structure shown in FIG. 2;and

FIG. 4 is a view similar to FIG. 2 and illustrating an alternateembodiment of the invention.

Referring now to the drawings in detail, the top portion of a reinforcedplastic material handling crate according to one embodiment of thepresent invention is indicated generally by the reference numeral 1 andis shown in FIG. 1 as having four integrally molded, verticallyextending plastic sidewall panels indicated generally by thereference'numerals 2, 3, 4 and 5, respectively. The vertical side panelsmay each be formed with a plurality of reinforcing, or stiffening ribs6, as desired, and a handle opening 7 may be formed in the respectiveside panels in the conventional manner.

The horizontal cross section of the crate chosen for illustrativepurposes is substantially rectangular and, in the embodiment shown inFIGS. l3, each of the side panels have integrally formed along theirupper edge a substantially L- shaped portion 9 including a substantiallyhorizontally extending flange portion 10 and a vertically extending bandportion 11, said flange and band portions cooperating to define a ledge12 extending around the inner periphery of the crate 1 adjacent the topor rim portion thereof. A plurality of generally rectangular openings 13extend horizontally through the band portion 11 at spaced intervalstherealong, with at least one, and preferably two or more openings 13being positioned intermediate the vertical side edges of each of therespective side panels.

An endless metal reinforcing rod member 15 is formed from a length ofthe steel rod shaped into a generally rectangular configuration byhaving its adjoining ends welded as at 16 to form a closed loop. Theouter periphery of reinforcing member 15 is substantially equal to andis shaped to conform to the inner periphery of the band portion 11 whenthe lower edge surface 17 of the reinforcing member is disposed upon theledge 12. The inner periphery of reinforcing rod 15 is shaped to form,in effect, a vertical continuation of the inner side surfaces of therespective side'panels, as illustrated in FIG. 2 of the drawings. Aplurality of tabs 18 are integrally formed on and project laterally fromthe outer peripheral surface of reinforcing rod member 15. Preferablytab members 18 are formed by coining a portion of the material from theouter edge of the steel rod. The tabs 18 have a generally rectangularcross section corresponding to the shape and size of the openings 13,with the tabs 18 being spaced to project one through each of therespective openings.

Reinforcing rod member 15 is dimensioned such that its upper edgesurface 19 is substantially flush with the top edge surface of the band11 so that the reinforcing rod member 15 forms a part of the top rimportion of the crate. In the event of impact loads applied to the toprim of the crate, as by dropping another crate thereon, or by strikingthe top edge of the crate against a hard surface while emptying orcleaning, the reinforcing rod member 15 will transmit the impact loadover a substantial area of the ledge 12 thereby protecting the plasticsidewalls at the top rim against breaking or excessive damage.

The reinforcing rod member 15 is equally effective in reinforcing thecrate for the usual purposes, i.e., providing the dimensional stabilityfor the top of the crate and reinforcing the sidewalls of the crateagainst lateral loads, as in the prior art devices. Since thereinforcing rod is dimensioned to fit snugly on the ledge 12 within band11, the outwardly extending horizontal tabs provide an effectiveinterlock positively retaining the reinforcing rim on the crate. In thisrespect, it is pointed out that the maximum lateral load normallyencountered, by such crates are impact loads from the outer surfacerather than pressure loads from the inside; therefore, placing thereinforcing rod element on the inner periphery of the crate providesmaximum reinforcing for the crate.

Referring now to FIG. 4 of the drawings, an alternate embodiment of theinvention is illustrated in which the inner peripheral surface of thesidewall are continuous, and the reinforcing rod retaining ledge 22 isformed by providing an outwardly projecting, substantially horizontalflange 23 extending around the outer periphery of the crate invertically spaced relation to the top edge thereof. A plurality ofgenerally rectangular openings 24 are formed in the sidewalls of thecrate between flange 23 and the top peripheral edge thereof, in positionto receive a plurality of inwardly extending tab members 25 on anendless reinforcing rod element 26. Tab members 25 are similar to tabmembers 18 on reinforcing rod member 15, but are formed on the innerrather than the outer periphery of the ring. In this embodiment it isnecessary to provide means for preventing the sidewalls of the cratefrom being defected inwardly away from the reinforcing rod member 26. Tothis end, a plurality of vertically extending generally rectangularopenings 27 are formed through the horizontally extending flange 23 inposition to receive an equal number of vertically extending tab members28 integrally formed on and projecting downwardly from the bottom edgeof reinforcing rod member 26. Thus, tabs 28 disposed in openings 27, andtabs 25 disposed in opening 24 cooperate to retain reinforcing rodmember 26 on the outer periphery of the crate and to prevent defectionof the sidewalls of the crate under the influence of lateral loads. Atthe same time, the top edge 29 of reinforcing rod 26 protects the toprim of the crate against impact loads in the manner similar to thatdescribed above with regard to the embodiment illustrated in FIGS. 1-3.Thus, it is apparent that various modifications of the invention may bemade while maintaining the concept of providing an exposed upper surfaceon the reinforcing rod member which forms a portion of the top rimsurface of the crate.

Accordingly, while preferred embodiments of my invention have beendisclosed and described, I wish it understood that I do not intend to berestricted solely thereto, but that I do intend to include allembodiments thereof which would be apparent to one skilled in the artand which come within the spirit and scope of my invention.

lclaim:

1. in a material handling crate having integrally molded plasticsidewalls and reinforcing means on said sidewalls adjacent the open topof the crate, the improvement wherein said reinforcing means comprisesan endless metal ring mounted on and extending around said crateadjacent the open top thereof and having an exposed upwardly directedsurface defining at least a portion of the top rim surface of the crate,and retaining means supporting said reinforcing ring in position on saidcrate, said retaining means including an integrally molded substantiallyhorizontal flange extending around said crate adjacent the open topthereof defining a substantially horizontal ledge positioned to engageand support a downwardly directed surface of said metal ring, saidhorizontal ledge being capable of transmitting vertical loads from saidmetal ring to said sidewalls, a band extending upwardly from said flangeand cooperating therewith to define a shoulder, and means interlockingsaid retaining means and said metal ring including a plurality ofopenings extending through said band at spaced intervals around saidcrate and a plurality of integrally formed tab portions on saidreinforcing ring extending through said openings and cooperating withsaid flange and said band to prevent substantial relative movementbetween said metal ring and said sidewalls of said crate.

2. In the material handling crate defined in claim 1, the furtherimprovement wherein the top edge surface of said band and said exposedupwardly directed surface cooperate to define the top rim surface ofsaid crate.

3. The material handling crate defined in claim 1, wherein said bandextends upwardly from the outer peripheral edge of said flange to definesaid shoulder for supporting said reinforcing ring around the innerperiphery at said crate at said open top.

4. The material handling crate defined in claim 3, wherein said openingsextend horizontally through said band and said tabs project outwardlyfrom the outer peripheral surface of said reinforcing ring in positionto project one through each of said openings to prevent said reinforcingring from being lifted vertically from said shoulder.

5. The material handling crate defined in claim 1, wherein said bandextends upwardly from the inner peripheral edge of said flange to definesaid shoulder for supporting said reinforc' ing ring around the outerperiphery of said crate at said open top, said band fonning in effect avertical continuation of said sidewalls above said flange.

6. The material handling crate defined in claim 5, wherein a portion ofsaid openings are extended horizontally through said band and a portionextend vertically through said flange, said reinforcing ring having aportion ofsaid tabs extending inward from the inner peripheral surfacethereof to extend through said openings in said band to prevent verticalmovement ofsaid reinforcing ring and a portion of said tabs extendingdownward through said openings in said flange to prevent said sidewallsfrom being deflected inward relative to said reinforcing ring.

k t I:

1. In a material handling crate having integrally molded plasticsidewalls and reinforcing means on said sidewalls adjacent the open topof the crate, the improvement wherein said reinforcing means comprisesan endless metal ring mounted on and extending around said crateadjacent the open top thereof and having an exposed upwardly directedsurface defining at least a portion of the top rim surface of the crate,and retaining means supporting said reinforcing ring in position on saidcrate, said retaining means including an integrally molded substantiallyhorizontal flange extending around said crate adjacent the open topthereof defining a substantially horizontal ledge positioned to engageand support a downwardly directed surface of said metal ring, saidhorizontal ledge being capable of transmitting vertical loads from saidmetal ring to said sidewalls, a band extending upwardly from said flangeand cooperating therewith to define a shoulder, and means interlockingsaid retaining means and said metal ring including a plurality ofopenings extending through said band at spaced intervals around saidcrate and a plurality of integrally formed tab portions on saidreinforcing ring extending through said openings and cooperating withsaid flange and said band to prevent substantial relative movementbetween said metal ring and said sidewalls of said crate.
 2. In thematerial handling crate defined in claim 1, the further improvementwherein the top edge surface of said band and said exposed upwardlydirected surface cooperate to define the top rim surface of said crate.3. The material handling crate deFined in claim 1, wherein said bandextends upwardly from the outer peripheral edge of said flange to definesaid shoulder for supporting said reinforcing ring around the innerperiphery at said crate at said open top.
 4. The material handling cratedefined in claim 3, wherein said openings extend horizontally throughsaid band and said tabs project outwardly from the outer peripheralsurface of said reinforcing ring in position to project one through eachof said openings to prevent said reinforcing ring from being liftedvertically from said shoulder.
 5. The material handling crate defined inclaim 1, wherein said band extends upwardly from the inner peripheraledge of said flange to define said shoulder for supporting saidreinforcing ring around the outer periphery of said crate at said opentop, said band forming in effect a vertical continuation of saidsidewalls above said flange.
 6. The material handling crate defined inclaim 5, wherein a portion of said openings are extended horizontallythrough said band and a portion extend vertically through said flange,said reinforcing ring having a portion of said tabs extending inwardfrom the inner peripheral surface thereof to extend through saidopenings in said band to prevent vertical movement of said reinforcingring and a portion of said tabs extending downward through said openingsin said flange to prevent said sidewalls from being deflected inwardrelative to said reinforcing ring.